1. Department of Obstetrics and Gynaecology, University Malaya Medical Centre Faculty of Medicine, University of Malaya, Kuala Lumpur, Malaysia.
2. Department of Obstetrics and Gynaecology, Mahkota Medical Centre, Melaka, Malaysia.
3. Department of Obstetrics and Gynecology, Chang Gung Memorial Hospital at Linkouter Medical Center and Chang Gung University College of Medicine, Kwei-Shan, Tao-Yuan, Taiwan.